Display controller, and method and computer-readable medium for the same

ABSTRACT

A display controller including a storage storing a list image including a plurality of object images, a display having a display area configured to concurrently display a particular number of object images, and a control unit configured to display the particular number of object images arranged along a particular direction in the display area, display a specific indication image indicating a specific direction along the particular direction, detect a dragging operation of dragging the specific indication image in the specific direction, detect a dragging operation amount of the detected dragging operation, and control the display such that the particular number of object images are scrolled in the particular direction at a scrolling speed, the scrolling speed being associated with the detected dragging operation amount.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119 from JapanesePatent Application No. 2014-135055 filed on Jun. 30, 2014. The entiresubject matter of the application is incorporated herein by reference.

BACKGROUND

1. Technical Field

The following description relates to one or more aspects of a displaycontroller configured to display a plurality of object images arrangedin a particular direction, and a method and a computer-readable mediumfor the display controller.

2. Related Art

In various types of information processing devices such asmulti-function peripherals and mobile information terminal devices,there is a case where a list image including object images arranged in arow is displayed on a display. Each object image represents acorresponding function or a corresponding setting item. When the objectimages included in the list image are too many to be displayed all atthe same time on the display, a part of the object images included inthe list image is displayed on the display.

In this case, as a method for displaying object images that are notdisplayed on the display, for instance, a method has been known forscrolling the list image by pressing and operating arrow keys providedat the information processing devices.

Further, for instance, a method has been known for scrolling the listimage by operating (e.g., tapping) arrow images displayed next to thelist image.

SUMMARY

The aforementioned known scrolling methods are not necessarilyuser-friendly. This is because it might take a long time before anintended object image is displayed on the display. In particular, as thelist image includes a larger number of the object images, it is morelikely to take a long time before the intended object image isdisplayed.

Aspects of the present disclosure are advantageous to provide one ormore techniques to improve user-friendliness of a display controllerwhen a user scrolls a list image displayed on a display.

According to aspects of the present disclosure, a display controller isprovided, the display controller including a storage configured to storea list image, the list image including a plurality of object images, adisplay having a display area, the display area being configured toconcurrently display a particular number of object images of theplurality of object images, and a control unit configured to display theparticular number of object images arranged along a particular directionin the display area, display a specific indication image in the displayarea, the specific indication image indicating a specific directionalong the particular direction, detect a dragging operation of draggingthe specific indication image in the specific direction, detect adragging operation amount of the detected dragging operation, andcontrol the display such that the particular number of object images arescrolled in the particular direction at a scrolling speed, the scrollingspeed being associated with the detected dragging operation amount.

According to aspects of the present disclosure, further provided is amethod adapted to be implemented on a processor coupled with a storageconfigured to store a list image, the list image including a pluralityof object images, and a display having a display area, the display areabeing configured to concurrently display a particular number of objectimages of the plurality of object images, the method includingdisplaying the particular number of object images arranged along aparticular direction in the display area, displaying a specificindication image in the display area, the specific indication imageindicating a specific direction along the particular direction,detecting a dragging operation of dragging the specific indication imagein the specific direction, detecting a dragging operation amount of thedetected dragging operation, and controlling the display such that theparticular number of object images are scrolled in the particulardirection at a scrolling speed, the scrolling speed being associatedwith the detected dragging operation amount.

According to aspects of the present disclosure, further provided is anon-transitory computer-readable medium storing computer-readableinstructions that are executable by a processor coupled with a storageconfigured to store a list image, the list image including a pluralityof object images, and a display having a display area, the display areabeing configured to concurrently display a particular number of objectimages of the plurality of object images, the instructions beingconfigured to, when executed by the processor, cause the processor todisplay the particular number of object images arranged along aparticular direction in the display area, display a specific indicationimage in the display area, the specific indication image indicating aspecific direction along the particular direction, detect a draggingoperation of dragging the specific indication image in the specificdirection, detect a dragging operation amount of the detected draggingoperation, and control the display such that the particular number ofobject images are scrolled in the particular direction at a scrollingspeed, the scrolling speed being associated with the detected draggingoperation amount.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

FIG. 1A is a block diagram schematically showing a configuration of amulti-function peripheral (hereinafter referred to as an “MFP”) in anillustrative embodiment according to one or more aspects of the presentdisclosure.

FIG. 1B is an external view of an operation panel of the MFP in theillustrative embodiment according to one or more aspects of the presentdisclosure.

FIG. 2A exemplifies a copy function setting screen in the illustrativeembodiment according to one or more aspects of the present disclosure.

FIG. 2B schematically shows a whole list image in the illustrativeembodiment according to one or more aspects of the present disclosure.

FIGS. 3A, 3B, 3C, and 3D illustrate a one of arrow icons to be extendedand contracted in response to being dragged in the illustrativeembodiment according to one or more aspects of the present disclosure.

FIGS. 4A, 4B, and 4C illustrate a relationship between a drag length bywhich the pressed arrow icon is dragged and a scrolling speed at whichthe list image is scrolled, in the illustrative embodiment according toone or more aspects of the present disclosure.

FIGS. 5A and 5B illustrate a bounding operation that the pressed arrowicon performs when the list image is scrolled up to where a tail endthereof in a scrolling direction appears in a list display area, in theillustrative embodiment according to one or more aspects of the presentdisclosure.

FIGS. 6A, 6B, and 6C illustrate a small bounding operation that thepressed arrow icon performs when the pressed arrow icon is furtherdragged in a state where the tail end of the list image in the scrollingdirection is already displayed in the list display area, in theillustrative embodiment according to one or more aspects of the presentdisclosure.

FIGS. 7, 8, and 9 are flowcharts showing a procedure of a displaycontrol process in the illustrative embodiment according to one or moreaspects of the present disclosure.

FIG. 10 exemplifies another list image in a modification according toone or more aspects of the present disclosure.

DETAILED DESCRIPTION

It is noted that various connections are set forth between elements inthe following description. It is noted that these connections in generaland, unless specified otherwise, may be direct or indirect and that thisspecification is not intended to be limiting in this respect. Aspects ofthe present disclosure may be implemented on circuits (such asapplication specific integrated circuits) or in computer software asprograms storable on computer-readable media including but not limitedto RAMs, ROMs, flash memories, EEPROMs, CD-media, DVD-media, temporarystorage, hard disk drives, floppy drives, permanent storage, and thelike.

Hereinafter, an illustrative embodiment according to aspects of thepresent disclosure will be described with reference to the accompanyingdrawings.

(1) Configuration of MFP

As shown in FIG. 1A, a multi-function peripheral 1 (hereinafter referredto as the “MFP 1” in an abbreviated form) of an illustrative embodimentincludes a CPU 11, a ROM 12, a RAM 13, a non-volatile random accessmemory 14 (hereinafter referred to as the “NVRAM 14”), an image readingunit 15, an image forming unit 16, an operation panel unit 17, a memorycard interface 18 (hereinafter, which may be referred to as the memorycard I/F 18), a network communication unit 19, and a telephonecommunication unit 20.

The CPU 11 is configured to take control of each element included in theMFP 1 in accordance with various programs stored in at least one of theROM 12 and the NVRAM 14. The RAM 13 is used as a work area for storingvarious kinds of information and as a main memory for storing imagedata. The NVRAM 14 is a non-volatile memory that is able to electricallyrewrite contents stored therein. The NVRAM 14 stores firmware, varioussetting values, programs, and various kinds of data. Specifically, forinstance, the NVRAM 14 stores a program for a below-mentioned displaycontrol process (see FIGS. 7 to 9), and data of a below-mentioned listimage 40 (see FIG. 2). It is noted that the program for the displaycontrol process and the data of the list image 40 may be stored in atleast one of the ROM 12 and the NVRAM 14.

The image reading unit 15 is configured to read an image of a documentsheet by an image sensor and generate image data expressing the readimage. The image forming unit 16 is configured to print an image on asheet-like recording medium (e.g., a recording paper). The memory cardI/F 18 is an interface into which various memory cards are attached. Thememory card I/F 18 is configured to control operations of writing datainto a memory card and reading data from the memory card. The networkcommunication unit 19 includes a network interface card. The networkcommunication unit 19 is configured to perform data communication withan external device by a particular communication system. The telephonecommunication unit 20 includes a modem. The telephone communication unit20 is used for voice communication and facsimile communication via atelephone line (not shown).

The operation panel unit 17 includes a liquid crystal display 21(hereinafter referred to as the “LCD 21” in an abbreviated form), atouchscreen 22, and an inside-illumination type display 23. The liquidcrystal display 21, the touchscreen 22, and the inside-illumination typedisplay 23 are disposed as shown in FIG. 1B. The LCD 21 is configured todisplay thereon various kinds of information such as the functions andan operational state of the MFP 1.

The touchscreen 22 is a transparent-film-shaped input device configuredto detect a touch (pressing) operation using an indication body such asa finger and a stylus. The touchscreen 22 is disposed on displaysurfaces of the LCD 21 and the inside-illumination type display 23 in anoverlapped (integrated) manner. In the illustrative embodiment, at leasttapping and dragging may be cited as detectable touch operations on thetouchscreen 22. The inside-illumination type display 23 is configured todisplay (images representing) numeric keypads and operable buttons.

The MFP 1 has major functions such as a facsimile function, a copyfunction, a scanning function, a digital camera print function, a cloudfunction, and a label print function. Each of these functions isactualized by the CPU 11 executing function programs stored in at leastone of the ROM 12 and the NVRAM 14.

(2) List Image

When the MFP 1 is in a particular standby state, a standby screen isdisplayed on the LCD 21. The standby screen displays thereon iconsrepresenting the aforementioned plurality of functions. When tapping anicon associated with an intended function, a user is allowed to use theintended function.

For instance, when the user wishes to use the copy function, the usertaps the icon representing the copy function. Thereby, the display onthe LCD 21 is changed to an execution screen for executing the copyfunction. The copy function is a function to cause the image readingunit 15 to read an image of a document sheet and cause the image formingunit 16 to print the read image. On the execution screen for the copyfunction, a setting button is displayed. The setting button is forconfiguring setting values of various setting items for the copyfunction. When the setting button is tapped, the display on the LCD 21is switched to a copy function setting screen 30 (hereinafter, which maysimply be referred to as a “setting screen 30”) exemplified in FIG. 2A.

As shown in FIG. 2A, on the setting screen 30, a list image 40 isdisplayed in a specific area (hereinafter referred to as a “list displayarea 31”) of the whole screen. The list image 40 includes a plurality ofitem buttons 40-1, 40-2, . . . arranged in vertical direction of thesetting screen 30.

More specifically, as shown in FIG. 2B, the list image 40 includesvertically-arranged n pieces of item buttons from a first item button40-1 to an n-th item button 40-n. The first item button 40-1 is an itembutton for setting a quality level of copied images. When the first itembutton 40-1 is tapped, the display on the LCD 21 is switched to a copyquality setting screen for setting the quality level of copied images.When an intended quality level is selected and fixed, the display on theLCD 21 is again switched to the setting screen 30 shown in FIG. 2A.

The second item button 40-2 is an item button for setting a sheet type.The third item button 40-3 is an item button for setting a sheet size.The fourth item button 40-4 is an item button for setting a way toselect a tray. The fifth item button 40-5 is an item button for settinga copy magnification. The sixth item button 40-6 is an item button forsetting a copy density. The seventh item button 40-7 is an item buttonfor making a choice between stack and sort.

Thus, the list image 40 includes the n pieces of item buttons 40-1 to40-n arranged. Meanwhile, on the setting screen 30, the maximum numberof item buttons displayable concurrently in the list display area 31 isfour as shown in FIGS. 2A and 2B. FIGS. 2A and 2B show an example inwhich the four item buttons 40-1 to 40-4 (including the first itembutton 40-1 as an uppermost item button) of the list image 40 aredisplayed on the setting screen 30.

To display an item button that is not displayed in the list display area31, the user has only to drag one of an upward arrow icon 33 and adownward arrow icon 34. The upward arrow icon 33 is an icon indicated byan arrow directed in an upward direction along the arrangement direction(i.e., the vertical direction) of the list image 40. The downward arrowicon 34 is an icon indicated by an arrow directed in a downwarddirection opposite to the direction of the upward arrow icon 33.

Each arrow icon 33 and 34, as a whole, is disposed to be adjacent to thelist image 40 displayed in the list display area 31 and be in a middleportion in the arrangement direction of the list image 40. Each arrowicon 33 and 34 has a particular initial length in an initial statebefore any touch operation by the indication body has not performed tothe arrow icons 33 and 34.

When the upward arrow icon 33 is dragged upward, the list image 40 isscrolled downward. Thereby, the icon buttons of the list image 40 to bedisplayed on the setting screen 30 make a transition to upper iconbuttons that are positioned at an upper side of the list. When thedownward arrow icon 34 is dragged downward, the list image 40 isscrolled upward. Thereby, the icon buttons of the list image 40 to bedisplayed on the setting screen 30 make a transition to lower iconbuttons that are positioned at a lower side of the list.

In the state exemplified in FIGS. 2A and 2B, the first item button 40-1as the uppermost item button is already displayed on the setting screen30. Therefore, even though the upward arrow icon 33 is further draggedupward in this state, the list image 40 is not scrolled downward sincethere is no item button above the first item button 40. Meanwhile, whenthe downward arrow icon 34 is dragged downward in the state exemplifiedin FIGS. 2A and 2B, the list image 40 is scrolled upward. Thereby, itembuttons positioned downstream in the list serially appear in the listdisplay area 31 on the setting screen 30. When the downward dragging ofthe downward arrow icon 34 is continued, the upward scrolling of thelist image 40 is continued. Then, when the n-th item button 40-n as thelowermost item button appears in the list display area 31, the scrollingis stopped.

(3) Scrolling Speed and Length of Each Arrow Icon

A scrolling speed at which the list image 40 is scrolled when each arrowicon 33 and 34 is dragged depends on a drag length Ld. The drag lengthLd represents a dragging operation amount when each arrow icon 33 and 34is dragged. Namely, the longer the drag length Ld is, the higher thescrolling speed is. In the illustrative embodiment, the drag length Ldis a vertical length component of the whole dragging operation amount.

Further, when each arrow icon 33 and 34 is dragged, the length of thedragged arrow icon is longer than the initial length thereof by a lengthcorresponding to the drag length Ld. In the illustrative embodiment, thelength of the dragged arrow icon is longer than the initial lengththereof by a length equivalent to the drag length Ld. Hereinafter,detailed explanations will be provided of the length of each arrow icon33 and 34 and the scrolling speed.

Firstly, an explanation will be provided of a relationship between anoperation of dragging the arrow icons 33 and 34 and the length of thearrow icons 33 and 34, with reference to FIGS. 3A to 3D. As shown inFIG. 3A, arrow pressing detection areas 33 a and 34 a are set for thearrow icons 33 and 34 in their initial states, respectively.Specifically, an upward-arrow pressing detection area 33 a is set forthe upward arrow icon 33. When a position within the upward-arrowpressing detection area 33 a is pressed (touched) by the indicationbody, tapping of the upward arrow icon 33 is detected. A downward-arrowpressing detection area 34 a is set for the downward arrow icon 34. Whena position within the downward-arrow pressing detection area 34 a ispressed (touched) by the indication body, tapping of the downward arrowicon 34 is detected.

As shown in FIG. 3B, suppose, for instance, that (a position within) theupward-arrow pressing detection area 33 a for the upward arrow icon 33is tapped by an indication body 46. Only tapping the upward-arrowpressing detection area 33 a does not cause any change in length of theupward arrow icon 33 or scrolling of the list image 40. It is noted thatan initial position set for the upward arrow icon 33 in FIG. 3B is a tipposition, in the vertical direction, of the upward arrow icon 33 withthe initial length in the initial state with an initial length.

When the indication body 46 is dragged upward after the upward arrowicon 33 is tapped by the indication body 46, as shown in FIG. 3C, theupward arrow icon 33 becomes longer than the initial length by anextension amount Lr corresponding to the drag length Ld (i.e., thedragging operation amount of the indication body 46). In theillustrative embodiment, the extension amount Lr is equivalent to thedrag length Ld (i.e., Lr=Ld). Further, as shown in FIG. 3C, during aperiod of time when the upward arrow icon 33 is being dragged by theindication body 46, the list image 40 is scrolled at a speedcorresponding to the drag length Ld.

When the indication body 46 is lifted up and separated away from thetouchscreen 22 in a state as shown in FIG. 3C where the upward arrowicon 33 has been dragged only by the drag length Ld, the upward arrowicon 33 is brought back to the initial state, as shown in FIG. 3D.Namely, the length of the upward arrow icon 33 returns to the initiallength. At this time, the scrolling of the list image 40 is stopped. Inthis regard, however, the scrolling of the list image 40 is not stoppedimmediately after the indication body 46 is lifted up away from thetouchscreen 22. In the illustrative embodiment, the scrolling speedgradually decreases after the indication body 46 is lifted up away fromthe touchscreen 22.

Hereinabove, operations to be executed in response to the upward arrowicon 33 being dragged have been described. Same applies to when thedownward arrow icon 34 is dragged, except for the dragging direction(i.e., the downward direction) at the time that is opposite to thedragging direction (i.e., the upward direction) of the upward arrow icon33.

Subsequently, an explanation will be provided of a relationship betweenthe drag length Ld and the scrolling speed, with reference to FIGS. 4Ato 4C. As described above, the longer the drag length Ld is, the higherthe scrolling speed of the list image 40 is. For instance, as shown inFIG. 4A, when the drag length Ld is equal to Ld1, the scrolling speed isV1 corresponding to the drag length Ld1. At this time, the length of theupward arrow icon 33 is longer than the initial length by an extensionamount Lr1 corresponding to the drag length Ld1.

When the drag length Ld is extended to Ld2 (which is longer than Ld1) byfurther moving the indication body 46 upward from the state shown inFIG. 4A, the scrolling speed increases to V2 corresponding to the draglength Ld2 as shown in FIG. 4B. At this time, the length of the upwardarrow icon 33 is further extended from the state shown in FIG. 4A, andconsequently becomes a length that is longer than the initial length byan extension amount Lr2 corresponding to the drag length Ld2.

When the drag length Ld is extended to Ld3 (which is longer than Ld2) byfurther moving the indication body 46 upward from the state shown inFIG. 4B, the scrolling speed increases to V3 corresponding to the draglength Ld3 as shown in FIG. 4C. At this time, the length of the upwardarrow icon 33 is further extended from the state shown in FIG. 4B, andconsequently becomes a length that is longer than the initial length byan extension amount Lr3 corresponding to the drag length Ld3.

It is possible to appropriately determine as needed how to actuallychange each arrow icon 33 and 34 in response to the change in the draglength Ld. For instance, the extension amount Lr of each arrow icon 33and 34 may be increased by a unit extension amount ΔLr every increase ofthe drag length Ld by a unit increase amount ΔLd. Further, for instance,the extension amount Lr may be continuously increased in response to theincrease of the drag length Ld. The extension amount Lr may be changedlinearly or nonlinearly with respect to the drag length Ld. Theaforementioned relationship between the drag length Ld and the extensionamount Lr may be applied to the relationship between the drag length Ldand the scrolling speed.

(4) Bounding Operation by Arrow Icons

When the scrolling of the list image 40 is continued by one of the arrowicons 33 and 34 being continuously dragged, an item button positioned atan end portion of the list image 40 is eventually displayed in the listdisplay area 31 on the setting screen 30, and the scrolling is stopped.At this time, in the illustrative embodiment, the color of the draggedarrow icon changes temporarily. Further, when the scrolling is stopped,even though the indication body 46 is still touching the touchscreen 22(i.e., even though the dragging by the indication body 46 is continued),the dragged arrow icon performs a bounding operation. Specifically, thedragged arrow icon returns to the initial state with the initial lengthfrom the state where the arrow icon is extended as long as a lengthcorresponding to the drag length Ld.

For instance, when the upward arrow icon 33 is dragged upward, the listimage 40 is scrolled downward. Thereby, the item buttons to be displayedon the setting screen 30 make a sequential transition to upper-side itembuttons of the list image 40. When the dragging of the upward arrow icon33 is further continued, as shown in FIG. 5A, the first item button 40-1positioned at the upper end of the list image 40 appears at the highestlevel of the list display area 31, and the scrolling is stopped at thatstate. At this time, the color of the upward arrow icon 33 changestemporarily (e.g., from an original color “white” to “red”). Then, asshown in FIG. 5B, the upward arrow icon 33 bounds such that the lengththereof returns to the initial length. As described above, the color ofthe upward arrow icon 33 changes temporarily. In this regard, it ispossible to appropriately determine as needed at which point of time thecolor of the upward arrow icon 33 should be returned to the originalcolor. For instance, the color of the upward arrow icon 33 may bechanged before the upward arrow icon 33 bounds. Further, the color ofthe upward arrow icon 33 may be returned to the original color after theupward arrow icon 33 has bounded (the length of the upward arrow icon 33has returned to the initial length). Alternatively, the changed color ofthe upward arrow icon 33 may be maintained for a while after the upwardarrow icon 33 has bounded (the length of the upward arrow icon 33 hasreturned to the initial length). Thereafter, the color of the upwardarrow icon 33 may be returned to the original color after a lapse of aparticular period of time.

In an end button displayed state where one of the uppermost item buttonand the lowermost item button of the list image 40 is already displayed,when the pressed arrow icon is further dragged in such a direction as toattempt to display an area further beyond the already-displayed one ofthe uppermost item button and the lowermost item button, the draggedarrow icon performs a small bounding operation.

As shown in FIG. 5A, suppose for instance that the first item button40-1 positioned at the upper end of the list image 40 appears at thehighest level of the list display area 31, and the scrolling is stoppedat that state. The state is an end stop state where the list image 40 isnot allowed to be scrolled downward anymore, i.e., where the list image40 remains stopped without being scrolled downward even though theupward arrow icon 33 is dragged upward.

In the end stop state, when the upward arrow icon 33 is tapped by theindication body 46 as shown in FIG. 6A and is dragged upward as shown inFIG. 6B, the upward arrow icon 33 is temporarily extended by a smallextension amount as shown in FIG. 6B. The small extension amount isfixed regardless of the drag length Ld. A period of time during whichthe upward arrow icon 33 is temporarily extended by the small extensionamount is a particular short period of time (e.g., 0.1 seconds).Further, the color of the upward arrow icon 33 temporarily changes inresponse to the upward arrow icon 33 being temporarily extended by thesmall extension amount.

After the upward arrow icon 33 is temporarily extended by the smallextension amount for the particular short period of time, the upwardarrow icon 33 bounds such that the length thereof returns to the initiallength as shown in FIG. 6B. In this regard, it is possible toappropriately determine as needed at which point of time the color ofthe upward arrow icon 33 should be returned to the original color. Forinstance, the changed color of the upward arrow icon 33 may bemaintained during the particular short period of time when the upwardarrow icon 33 is temporarily extended by the small extension amount.Further, the color of the upward arrow icon 33 may be returned to theoriginal color in response to the upward arrow icon 33 bounding.Alternatively, the changed color of the upward arrow icon 33 may bemaintained for a while after the upward arrow icon 33 has bounded, andthereafter, the color of the upward arrow icon 33 may be returned to theoriginal color.

(5) Display Control Process

Subsequently, referring to FIGS. 7 to 9, an explanation will be providedof a display control process to be executed by the CPU 11 of the MFP 1.The display control process includes the aforementioned operations suchas scrolling the list image 40 and extending and contracting the pressedarrow icon. After being activated, the CPU 11 loads a program for thedisplay control process exemplified in FIGS. 7 to 9 from the NVRAM 14and executes the program.

When starting the display control process shown in FIGS. 7 to 9, the CPU11 controls the LCD 21 to display the setting screen 30 (S100).Actually, when the display control process is started, a home screen isfirst displayed. Thereafter, via one or more particular screentransition operations performed on the home screen, the setting screen30 is displayed. In the display control process shown in FIGS. 7 to 9,operations related to screen transition to be executed until the settingscreen 30 is displayed are omitted.

In S110, the CPU 11 executes an event accepting operation. In theillustrative embodiment, depending on a contact state between theindication body 46 and the touchscreen 22, an event such as a pressingevent, a moving event, or a separating event is irregularly caused.Further, a screen updating event is regularly caused. In S110, when oneof the aforementioned events is caused, the CPU 11 accepts the causedevent.

In S120, the CPU 11 determines whether the CPU 11 has accepted thepressing event in S110. The pressing event is caused when a position onthe touchscreen 22 is tapped (pressed) by the indication body 46. Whendetermining that the CPU 11 has accepted the pressing event in S110(S120: Yes), the CPU 11 goes to S130. In S130, the CPU 11 determineswhether the pressed position (the position tapped by the indication body46) on the touchscreen 22 is within one of arrow pressing detectionareas. For instance, when the list image 40 and the arrow icons 33 and34 are displayed on the LCD 21 as exemplified in FIG. 2A, the CPU 11determines whether the pressed position is within one of the arrowpressing detection areas 33 a and 34 a (see FIG. 3A). When determiningthat the pressed position (the position tapped by the indication body46) on the touchscreen 22 is not within one of the arrow pressingdetection areas (S130: No), the CPU 11 goes to S160. It is noted thatwhen any arrow icon is not displayed on the LCD 21, the CPU 11 makes anegative determination (S130: No) and goes to S160. In S160, the CPU 11executes a regular pressing operation. Specifically, the CPU 11 executesan operation corresponding to an image displayed in the pressedposition. After execution of the regular pressing operation in S160, theCPU 11 goes back to S110.

When determining in S103 that the pressed position (the position tappedby the indication body 46) on the touchscreen 22 is within one of thearrow pressing detection areas (S130: Yes), the CPU 11 goes to S140. InS140, the CPU 11 executes a list moving mode transition operation.Specifically, the CPU 11 sets an operation mode of the MFP 1 to a listmoving mode. In S150, the CPU 11 executes a pressed position storingoperation. Specifically, the CPU 11 stores coordinates of the positiontapped by the indication body 46. After S150, the CPU 11 goes back toS110. It is noted that when the CPU 11 makes the affirmativedetermination in S130 (S130: Yes), the LCD 21 is in a state where thelist image 40 and the arrow icons 33 and 34 are displayed thereon asexemplified in FIG. 2A.

When determining in S120 that the CPU 11 has not accepted the pressingevent in S110 (S120: No), the CPU 11 goes to S170. In S170, the CPU 11determines whether the CPU 11 has accepted a moving event in S110. Themoving event is an event caused when the indication body 46 is moved(dragged) over a particular distance while being in contact with thetouchscreen 22.

When determining that the CPU 11 has accepted a moving event in S110(S170: Yes), the CPU 11 goes to S180. In S180, the CPU 11 determineswhether the operation mode is set to the list moving mode. Whendetermining that the operation mode is not set to the list moving mode(S180: No), the CPU 11 goes to S220. In S220, the CPU 11 executes aregular moving operation. Specifically, the CPU 11 executes a particularoperation corresponding to the indication body 46 being dragged in anarea outside the arrow icons 33 and 34. After execution of the regularmoving operation in S220, the CPU 11 goes back to S110.

When determining in S180 that the operation mode is set to the listmoving mode (S180: Yes), the CPU 11 goes to S190. In S190, the CPU 11stores a pressed-position difference between the pressed position storedin S150 and the current position pressed by the indication body 46 (apressed-position difference storing operation). More specifically, thepressed-position difference represents a component, in the directionindicated by the pressed arrow icon (that is along the arrangementdirection of the item buttons of the list image 40 and a scrollingdirection of the list image 40), of a distance between the pressedposition stored in S150 and the current position pressed by theindication body 46. In other words, the operation in S190 includesdetecting and storing the drag length Ld (see FIG. 3).

In S200, based on the pressed-position difference (i.e., the drag lengthLd) stored in S190, the CPU 11 determines a list moving speed, i.e., thescrolling speed for the list image 40 (a list moving speed determiningoperation). In S210, the CPU 11 executes a list moving speed storingoperation, i.e., stores the list moving speed determined in S200. AfterS210, the CPU 11 goes back to S110.

When determining in S170 that the CPU 11 has not accepted a moving eventin S110 (S170: No), the CPU 11 goes to S230. In S230, the CPU 11determines whether the CPU 11 has accepted a separating event. Theseparating event is an event caused when the contact between theindication body 46 and the touchscreen 22 is released, i.e., when theindication body 46 is lifted up and separated away from the touchscreen22.

When determining that the CPU 11 has accepted a separating event (S230:Yes), the CPU 11 goes to S240. In S240, the CPU 11 determines whetherthe operation mode is set to the list moving mode. When determining thatthe operation mode is not set to the list moving mode (S240: No), theCPU 11 goes to S270. In S270, the CPU 11 executes a regular separatingoperation. Specifically, the CPU 11 executes a particular operationcorresponding to the indication body 46 being separated away from thetouchscreen 22 in an area outside the arrow icons 33 and 34. Afterexecution of the regular separating operation in S270, the CPU 11 goesback to S110.

When determining in S240 that the operation mode is set to the listmoving mode (S240: Yes), the CPU 11 goes to S250. In S250, the CPU 11initializes the pressed-position difference (i.e., the drag length Ld)between the pressed position stored in S150 and the current positionpressed by the indication body 46 (a pressed-position differenceinitializing operation). Specifically, the CPU 11 sets thepressed-position difference to zero. In S260, the CPU 11 executes a listmoving termination mode transition operation. Specifically, the CPU 11sets the operation mode to a list moving termination mode. After S260,the CPU 11 goes back to S110.

When determining in S230 that the CPU 11 has not accepted a separatingevent (S230: No), the CPU 11 goes to S280 (see FIG. 8). As shown in FIG.8, in S280, the CPU 11 determines whether the CPU 11 has accepted ascreen updating event in S110. The screen updating event is an eventcaused regularly (e.g., every 50 msec) to switch the screen displayed onthe LCD 21 at a particular frame rate (e.g., 20 fps).

When determining that the CPU 11 has not accepted a screen updatingevent in S110 (S280: No), the CPU 11 goes back to S110. Meanwhile, whendetermining that the CPU 11 has accepted a screen updating event in S110(S280: Yes), the CPU 11 goes to S290. In S290, the CPU 11 determineswhether the operation mode is set to the list moving mode. Whendetermining that the operation mode is set to the list moving mode(S290: Yes), the CPU 11 goes to S300. In S300, the CPU 11 executes alist moving speed acquiring operation. Specifically, the CPU 11 acquiresthe list moving speed stored in S210. In S310, based on the list movingspeed acquired in S300, the CPU 11 executes a list moving amountdetermining operation, i.e., determines a list moving amount (i.e., ascrolling amount). The list moving amount determined in S310 is a movingdistance per unit cycle of the periodically-caused screen updatingevent. In S310, the CPU 11 sets a larger value of the list moving amountas the moving speed is higher (as the drag length Ld is longer).

In S320, the CPU 11 determines whether it is possible to move (scroll)the list image 40 by the list moving amount determined in S310. Whendetermining that it is possible to move the list image 40 by the listmoving amount determined in S310 (i.e., when determining that the tailend of the list image 40 in the scrolling direction still would notappear in the list display area 31 after the list image 40 is scrolledby the list moving amount determined in S310) (S320: Yes), the CPU 11goes to S370.

Meanwhile, when determining that it is not possible to move the listimage 40 by the list moving amount determined in S310 (i.e., whendetermining that the tail end of the list image 40 in the scrollingdirection would appear in the list display area 31 such that the listimage 40 is not allowed to be scrolled anymore before anactually-scrolled amount of the list image 40 reaches the list movingamount determined in S310) (S320: No), the CPU 11 goes to S330.

In S330, the CPU 11 again determines the list moving amount within alist movable range. Namely, the CPU 11 determines a maximum list movableamount up to which the list image 40 is allowed to be scrolled. In S340,the CPU 11 executes a pressed-position difference initializingoperation. Specifically, the CPU 11 initializes the pressed-positiondifference (i.e., the drag length Ld) between the pressed positionstored in S150 and the current position pressed by the indication body46. Specifically, the CPU 11 sets the pressed-position difference tozero. Namely, even in a state where the pressed arrow icon is actuallybeing dragging by the indication body 46, the CPU 11 forcibly sets thedrag length Ld to zero based on the determination that the tail end ofthe list image 40 in the scrolling direction would appear in the listdisplay area 31 before the actually-scrolled amount of the list image 40reaches the list moving amount determined in S310. As a result of theinitializing of the pressed-position difference, the bounding operationby the pressed arrow icon is achieved.

In S350, the CPU 11 executes a forcible termination mode transitionoperation. Specifically, the CPU 11 sets the operation mode to aforcible termination mode. In S360, the CPU 11 performs an arrow colorchanging operation. Specifically, the CPU 11 makes a setting change forthe color of the pressed arrow icon from an initial value (e.g., white)to a particular different color (e.g., red).

In S370, the CPU 11 determines an arrow length (i.e., a length of thepressed arrow icon) based on the pressed-position difference (i.e., thedrag length Ld) between the pressed position stored in S150 and thecurrent position pressed by the indication body 46. Specifically, theCPU 11 determines the extension amount Lr of the pressed arrow iconbased on the drag length Ld. In the illustrative embodiment, asdescribed above, the extension amount Lr is determined to be identicalto the drag length Ld. It is noted that when the pressed-positiondifference has been initialized by the operation in S340, the extensionamount Lr is determined to be zero.

In S380, the CPU 11 executes an LCD drawing operation. Specifically, theCPU 11 controls the LCD 21 to display the list image 40 moved by thelist moving amount determined in S310. In this respect, nonetheless,when determining the list moving amount in S330 (i.e., when determiningthat the list image 40 would be scrolled up to where the tail endthereof in the scrolling direction appears in the list display area 31),the CPU 11 controls the LCD 21 to display the list image 40 moved onlyby the list moving amount determined in S330. In this case, in the listdisplay area 31 on the setting screen 30, the item button positioned ata tail end portion of the list image 40 in the scrolling direction isdisplayed, and a state is shown in which the list image 40 has beenscrolled up to where the tail end thereof in the scrolling directionappears in the list display area 31.

Further, in S380, the CPU 11 changes the length of the pressed arrowicon to the arrow length determined in S370. At this time, when thearrow length is determined to be the initial length in S370 in responseto the pressed-position difference being initialized in S340, the arrowlength returns to the initial length (i.e., the pressed arrow iconbounds). Further, in S380, when the setting change has been made for thecolor of the pressed arrow icon in S360, the CPU 11 displays the pressedarrow icon with the changed color. It is noted that the color of thepressed arrow icon may be changed before or after the pressed arrow iconbounds (i.e., the length of the pressed arrow icon returns to theinitial length). Further, it is possible to appropriately determine asneeded how long the changed color of the pressed arrow icon should bemaintained after the color of the pressed arrow icon is changed, thougha corresponding operation is not shown in any of FIGS. 7 to 9. AfterS380, the CPU 11 goes back to S110.

When determining in S290 that the operation mode is not set to the listmoving mode (S290: No), the CPU 11 goes to S390. In S390, the CPU 11determines whether the operation mode is set to the list movingtermination mode. When determining that the operation mode is set to thelist moving termination mode (S390: Yes), the CPU 11 goes to S400. InS400, the CPU 11 executes a list moving speed determining operation.Specifically, the CPU 11 updates the list moving speed to a speed thatis a particular amount lower than the current stored speed. It is notedthat when the speed updated to be the particular amount lower than thecurrently-stored speed is a negative value, the CPU 11 updates the listmoving speed to zero. In S410, the CPU 11 executes a list moving speedstoring operation, i.e., stores the new list moving speed updated inS400.

In S420, the CPU 11 determines whether the list moving speed stored inS410 is zero. When determining that the list moving speed stored in S410is zero (S420: Yes), the CPU 11 goes to S480. In S480, the CPU 11 setsthe operation mode to a regular mode (a regular mode transitionoperation). After S480, the CPU 11 goes back to S110. When determiningin S420 that the list moving speed stored in S410 is not zero (S420:Yes), the CPU 11 goes to S430.

In S430, based on the list moving speed determined in S400, the CPU 11determines a list moving amount (i.e., a scrolling amount) in the samemanner as in S310. In S440, the CPU 11 determines whether it is possibleto move (scroll) the list image 40 by the list moving amount determinedin S430. When determining that it is possible to move the list image 40by the list moving amount determined in S430 (i.e., when determiningthat the tail end of the list image 40 in the scrolling direction stillwould not appear in the list display area 31 after the list image 40 isscrolled by the list moving amount determined in S430) (S440: Yes), theCPU 11 goes to S460.

Meanwhile, when determining that it is not possible to move the listimage 40 by the list moving amount determined in S430 (i.e., whendetermining that the tail end of the list image 40 in the scrollingdirection would appear in the list display area 31 such that the listimage 40 is not allowed to be scrolled anymore before theactually-scrolled amount of the list image 40 reaches the list movingamount determined in S430) (S440: No), the CPU 11 goes to S450.

In S450, the CPU 11 again determines the list moving amount within alist movable range in the same manner as in S330. Namely, the CPU 11determines a maximum list movable amount up to which the list image 40is allowed to be scrolled. In S460, the CPU 11 executes an arrow lengthinitializing operation. Specifically, the CPU 11 sets the length of thepressed arrow icon to the initial length.

In S470, the CPU 11 executes an LCD drawing operation. Specifically, theCPU 11 controls the LCD 21 to display the list image 40 moved by thelist moving amount determined in S430 or S450. Further, in S470, the CPU11 sets the length of the pressed arrow icon back to the initial lengthdetermined in S460. After S470, the CPU 11 goes back to S110. Whendetermining in S390 that the operation mode is not set to the listmoving termination mode (S390: No), the CPU 11 goes to S490 (see FIG.9).

As shown in FIG. 9, in S490, the CPU 11 determines whether the operationmode is set to the forcible termination mode. When determining that theoperation mode is not set to the forcible termination mode (S490: No),the CPU 11 goes to S530. In S530, the CPU 11 executes a regular drawingupdating operation. Thereafter, the CPU 11 goes back to S110.

When determining in S490 that the operation mode is set to the forcibletermination mode (S490: Yes), the CPU 11 goes to S500. In S500, the CPU11 executes an arrow length changing operation. The arrow lengthchanging operation is an operation for actualizing the small boundingoperation described with reference to FIGS. 6A to 6C. Specifically, inthe small bounding operation, the CPU 11 changes the current length ofthe pressed arrow icon by a change amount corresponding to a singleframe of screen. In the illustrative embodiment, the CPU 11 changes thecurrent length of the pressed arrow icon to a length after 50 msec. Whenthe CPU 11 advances to S500 for the first time after the operation modeis set to the forcible termination mode, the CPU 11 changes the lengthof the pressed arrow icon to a length that is a small amount longer thanthe initial length. Meanwhile, when the length of the pressed arrow iconhas already been changed to the length that is the small extensionamount longer than the initial length after the CPU 11 repeatedlyexecuted the operation in S500 in the forcible termination mode, the CPU11 changes the length of the pressed arrow icon to a length that is asmall amount shorter than the current length, so as to bound (the lengthof) the pressed arrow icon. Accordingly, as a result of repeatedlyexecution of the operation in S500, the pressed arrow icon performs thesmall bounding operation.

In S510, the CPU 11 determines whether the small bounding operation hasbeen completed, i.e., whether the length of the pressed arrow icon hasreturned to the initial length. When determining that the small boundingoperation has not been completed (S510: No), the CPU 11 goes back toS110. When determining that the small bounding operation has beencompleted (S510: Yes), the CPU 11 goes to S520. In S520, the CPU 11 setsthe operation mode to the regular mode (the regular mode transitionoperation). After S520, the CPU 11 goes back to S110.

Suppose, for instance, that specifications of the small boundingoperation are set such that the length of the pressed arrow icon changesby an amount ΔLo/2 each time the screen updating event occurs. It isnoted that ΔLo represents the small extension amount. In this case, whenthe CPU 11 advances to S500 for the first time, the length of thepressed arrow icon is set to a length (the initial length+ΔLo/2) that isΔLo/2 longer than the initial length. When the CPU 11 advances to S500again after occurrence of another screen updating event, the length ofthe pressed arrow icon is set to a length (the initial length+ΔLo) thatis further extended by ΔLo/2. At this time, for instance, the color ofthe pressed arrow icon may be temporarily changed. When the CPU 11advances to S500 again after occurrence of a further screen updatingevent, the length of the pressed arrow icon is set to the length (theinitial length+ΔLo/2) that is shortened by ΔLo/2. At this time, forinstance, the color of the pressed arrow icon may be returned to theoriginal color. When the CPU 11 advances to S500 again after occurrenceof a further screen updating event, the length of the pressed arrow iconis further shortened by ΔLo/2 and set to the initial length. Thereby,the small bounding operation is completed. Namely, in this example, thesmall bounding operation is performed through the four screen updatingevents.

In the display control process shown in FIGS. 7 to 9, the list image 40is scrolled in response to the pressed arrow icon being dragged. Then,when the list image 40 is scrolled up to where the tail end thereof inthe scrolling direction appears in the list display area 31, thepressed-position difference is initialized, and the pressed arrow iconis bounded. In this case, since the operation mode is set to theforcible termination mode in S350, the pressed arrow icon is oncereturned to the initial length by the above bounding, and thereafterperforms the small bounding operation only once via the operations inS490 and the following steps. In this respect, nonetheless, theaforementioned operations, in which the pressed arrow icon once returnsto the initial length and thereafter performs the small boundingoperation when the list image is scrolled up to where the tail endthereof in the scrolling direction appears in the list display area 31,are just an example. When the list image is scrolled up to where thetail end thereof in the scrolling direction appears in the list displayarea 31, the pressed arrow icon may only perform a bounding operation ofsimply returning to the initial length.

(6) Advantageous Effects

According to the MFP 1 of the aforementioned illustrative embodiment,when the upward arrow icon 33 or the downward arrow icon 34 is dragged,the list image 40 is scrolled at a speed corresponding to the draglength Ld. Namely, by adjusting the drag length Ld, it is possible toadjust the scrolling speed. Therefore, it is possible to achieveimproved operability and user-friendliness in scrolling of the listimage 40.

In the illustrative embodiment, the scrolling speed for the list image40 is higher as the drag length Ld is longer. Thereby, the user isallowed to make the scrolling speed higher by making the drag length Ldlarger and make the scrolling speed lower by making the drag length Ldsmaller. Therefore, the user is allowed to adjust the scrolling speed byan intuitive operation.

In the illustrative embodiment, each arrow icon 33 and 34 is set to theinitial length in the initial state where each arrow icon 33 and 34 hasnot been dragged. When one of the arrow icons 33 and 34 is dragged, thelength of the dragged arrow icon is changed to a length corresponding tothe drag length Ld. Specifically, the longer the drag length Ld, thelarger the extension amount Lr of the pressed arrow icon is. In theillustrative embodiment, the drag length Ld is equal to the extensionamount Lr of the pressed arrow icon.

Thus, the length of each arrow icon 33 and 34 varies depending on thedrag length Ld (i.e., depending on the scrolling speed for the listimage 40). Therefore, the user is allowed to intuitively grasp thescrolling speed for the list image 40 by viewing the length of thepressed arrow icon. Therefore, the user is allowed to easily adjust thescrolling speed for the list image 40.

In the illustrative embodiment, when the list image 40 is scrolled up towhere the tail end thereof in the scrolling direction appears in thelist display area 31, the scrolling of the list image 40 is stopped, andthe length of the pressed arrow icon returns to the initial length.Therefore, the user is allowed to easily recognize that the list image40 has been scrolled up to where the tail end thereof in the scrollingdirection appears in the list display area 31, by acknowledging that thescrolling of the list image 40 has been stopped and that the length ofthe pressed arrow icon has been initialized.

In the illustrative embodiment, when the pressed arrow icon is furtherdragged in the end button displayed state in which the list image 40 hasalready been scrolled up to where the item button positioned a tail endportion of the list image 40 in the scrolling direction appears in thelist display area 31, the pressed arrow icon performs the small boundingoperation. By acknowledging the small bounding operation, the user isallowed to easily recognize that the list image 40 has already beenscrolled up to where the tail end thereof in the scrolling directionappears in the list display area 31.

Hereinabove, the illustrative embodiment according to aspects of thepresent disclosure has been described. The present disclosure can bepracticed by employing conventional materials, methodology andequipment. Accordingly, the details of such materials, equipment andmethodology are not set forth herein in detail. In the previousdescriptions, numerous specific details are set forth, such as specificmaterials, structures, chemicals, processes, etc., in order to provide athorough understanding of the present disclosure. However, it should berecognized that the present disclosure can be practiced withoutreapportioning to the details specifically set forth. In otherinstances, well known processing structures have not been described indetail, in order not to unnecessarily obscure the present disclosure.

Only an exemplary illustrative embodiment of the present disclosure andbut a few examples of their versatility are shown and described in thepresent disclosure. It is to be understood that the present disclosureis capable of use in various other combinations and environments and iscapable of changes or modifications within the scope of the inventiveconcept as expressed herein. For instance, according to aspects of thepresent disclosure, the following modifications are possible.

[Modifications]

(1) List images to which aspects of the present disclosure areapplicable are not limited to the list image 40 exemplified in FIGS. 2Aand 2B. Object images that form the list image are not limited to theitem buttons 40-1 to 40-n exemplified in FIGS. 2A and 2B. Further,arrangement directions of the object images are not limited to thearrangement direction of the item buttons 40-1 to 40-n exemplified inFIGS. 2A and 2B. Aspects of the present disclosure may be applied toevery type of display controller configured to display on a display apart of a list image including a plurality of object images arranged ina particular arrangement direction, scroll the list image, and changeobject images displayed on the display.

For instance, aspects of the present disclosure may be applied to asetting screen 60 as exemplified in FIG. 10. On the setting screen 60shown in FIG. 10, a list image 70 is displayed in a list display area61. The list image 70 is formed by a plurality of menu icons 70-1, 70-2,70-3, . . . arranged in a left-to-right direction. The list image 70includes four or more menu icons. Nonetheless, a maximum number of menuicons concurrently displayable in the list display area 61 is three.Therefore, in order to display other menu icons that are not displayedin the list display area 61, it is required to scroll the list image 70in the left-to-right direction.

The list image 70 is scrolled in the left-to-right direction in responseto one of a leftward arrow icon 63 and a rightward arrow icon 64 beingdragged. Specifically, when the leftward arrow icon 63 is draggedleftward, the whole list image 70 is scrolled rightward. Thereby,contents of the list image 70 displayed on the setting screen 60 make atransition to left-side menu icons (i.e., left-side menu icons that havenot displayed appear on the setting screen 60). Meanwhile, when therightward arrow icon 64 is dragged rightward, the whole list image 70 isscrolled leftward. Thereby, the contents of the list image 70 displayedon the setting screen 60 make a transition to right-side menu icons(i.e., right-side menu icons that have not displayed appear on thesetting screen 60).

In the same manner as exemplified in the aforementioned illustrativeembodiment, the setting screen 60 may be configured such that ascrolling speed for the list image 70 varies depending on a drag lengthof the pressed arrow icon. Further, the setting screen 60 may beconfigured such that a length of the pressed arrow icon varies dependingon the drag length of the pressed arrow icon. Moreover, with respect toa bounding operation, a small bounding operation, and a color change ofthe pressed arrow icon, the setting screen 60 may be configured in thesame manner as exemplified in the aforementioned illustrativeembodiment.

(2) A shape and a size of each arrow icon may be determinedappropriately as needed. Further, a relative display position of eacharrow icon with respect to the list image on the LCD 21 may bedetermined appropriately as needed. Further, the upward arrow icon andthe downward arrow icon do not necessarily have to be displayed apartfrom each other. The upward arrow icon and the downward arrow icon maybe displayed as a single two-way arrow that indicates mutually-oppositetwo directions. Furthermore, in the first place, any arrow icon does notnecessarily have to be displayed. Instead, icons having a shapedifferent from an arrow may be displayed.

(3) Operations to the arrow icons for scrolling the list image are notlimited to dragging by the indication body 46 on the touchscreen 22. Forinstance, the list image may be scrolled by other moving operations suchas flicking the arrow icons and swiping the arrow icons.

Further, instead of the touch operation on the touchscreen 22, otherinput methods may be used to drag the arrow icons. For instance, thelist image may be scrolled when one of the arrow icons is dragged with amouse pointer.

(4) Aspects of the present disclosure may be applied not only to the MFP1 but also to any type of information processing terminal device thatincludes a display and is configured to display the list image on thedisplay.

What is claimed is:
 1. A display controller comprising: a storageconfigured to store a list image, the list image comprising a pluralityof object images; a display having a display area, the display areabeing configured to concurrently display a particular number of objectimages of the plurality of object images; and a control unit configuredto: display the particular number of object images arranged along aparticular direction in the display area; display a specific indicationimage in the display area, the specific indication image indicating aspecific direction along the particular direction; detect a draggingoperation of dragging the specific indication image in the specificdirection; detect a dragging operation amount of the detected draggingoperation; and control the display such that the particular number ofobject images are scrolled in the particular direction at a scrollingspeed, the scrolling speed being associated with the detected draggingoperation amount.
 2. The display controller according to claim 1,wherein the control unit is further configured to set the scrollingspeed such that the particular number of object images are scrolledfaster as the detected dragging operation amount increases.
 3. Thedisplay controller according to claim 1, wherein the control unit isfurther configured to: when not detecting the dragging operation ofdragging the specific indication image in the specific direction, set alength of the specific indication image in the specific direction to aspecific initial length; and when detecting the dragging operation ofdragging the specific indication image in the specific direction, set alength of the specific indication image in the specific direction fromthe specific initial length to a specific target length, the specifictarget length being associated with the detected dragging operationamount.
 4. The display controller according to claim 3, wherein thecontrol unit is further configured to set the specific target lengthlonger as the detected dragging amount is larger.
 5. The displaycontroller according to claim 3, wherein the control unit is furtherconfigured to: when a tail-end object image positioned at a tail endportion of the list image in the scrolling direction appears in thedisplay area and reaches a particular position in response to the listimage being scrolled in the scrolling direction, stop the scrolling ofthe list image; and when stopping the scrolling of the particular numberof object images, return the length of the specific indication image tothe specific initial length.
 6. The display controller according toclaim 5, wherein the control unit is further configured to, whenstopping the scrolling of the particular number of object images, changea color of the specific indication image.
 7. The display controlleraccording to claim 5, wherein the control unit is further configured to,when the dragging operation of dragging the specific indication image inthe specific direction is performed in a state where the tail-end objectimage positioned at the tail end portion of the list image in thescrolling direction is displayed in the particular position in thedisplay area, execute an extending-contracting operation of: extendingthe length of the specific indication image by a particular length for aparticular period of time; and thereafter returning the length of thespecific indication image to the specific initial length.
 8. The displaycontroller according to claim 7, wherein the control unit is furtherconfigured to, when executing the extending-contracting operation,change a color of the specific indication image.
 9. The displaycontroller according to claim 1, wherein the control unit comprises: aprocessor; and a memory storing a processor-executable instructionsconfigured to, when executed by the processor, cause the processor to:display the particular number of object images in the display area;display the specific indication image in the display area; detect thedragging operation of dragging the specific indication image in thespecific direction; detect the dragging operation amount of the detecteddragging operation; and control the display such that the particularnumber of object images are scrolled in the particular direction at thescrolling speed associated with the detected dragging operation amount.10. A method adapted to be implemented on a processor coupled with: astorage configured to store a list image, the list image comprising aplurality of object images; and a display having a display area, thedisplay area being configured to concurrently display a particularnumber of object images of the plurality of object images, the methodcomprising: displaying the particular number of object images arrangedalong a particular direction in the display area; displaying a specificindication image in the display area, the specific indication imageindicating a specific direction along the particular direction;detecting a dragging operation of dragging the specific indication imagein the specific direction; detecting a dragging operation amount of thedetected dragging operation; and controlling the display such that theparticular number of object images are scrolled in the particulardirection at a scrolling speed, the scrolling speed being associatedwith the detected dragging operation amount.
 11. A non-transitorycomputer-readable medium storing computer-readable instructions that areexecutable by a processor coupled with: a storage configured to store alist image, the list image comprising a plurality of object images; anda display having a display area, the display area being configured toconcurrently display a particular number of object images of theplurality of object images, the instructions being configured to, whenexecuted by the processor, cause the processor to: display theparticular number of object images arranged along a particular directionin the display area; display a specific indication image in the displayarea, the specific indication image indicating a specific directionalong the particular direction; detect a dragging operation of draggingthe specific indication image in the specific direction; detect adragging operation amount of the detected dragging operation; andcontrol the display such that the particular number of object images arescrolled in the particular direction at a scrolling speed, the scrollingspeed being associated with the detected dragging operation amount. 12.The non-transitory computer-readable medium according to claim 11,wherein the instructions are further configured to, when executed by theprocessor, cause the processor to set the scrolling speed such that theparticular number of object images are scrolled faster as the detecteddragging operation amount increases.
 13. The non-transitorycomputer-readable medium according to claim 11, wherein the instructionsare further configured to, when executed by the processor, cause theprocessor to: when not detecting the dragging operation of dragging thespecific indication image in the specific direction, set a length of thespecific indication image in the specific direction to a specificinitial length; and when detecting the dragging operation of draggingthe specific indication image in the specific direction, set a length ofthe specific indication image in the specific direction from thespecific initial length to a specific target length, the specific targetlength being associated with the detected dragging operation amount. 14.The non-transitory computer-readable medium according to claim 13,wherein the instructions are further configured to, when executed by theprocessor, cause the processor to set the specific target length longeras the detected dragging amount is larger.
 15. The non-transitorycomputer-readable medium according to claim 13, wherein the instructionsare further configured to, when executed by the processor, cause theprocessor to: when a tail-end object image positioned at a tail endportion of the list image in the scrolling direction appears in thedisplay area and reaches a particular position in response to the listimage being scrolled in the scrolling direction, stop the scrolling ofthe list image; and when stopping the scrolling of the particular numberof object images, return the length of the specific indication image tothe specific initial length.
 16. The non-transitory computer-readablemedium according to claim 15, wherein the instructions are furtherconfigured to, when executed by the processor, cause the processor to,when stopping the scrolling of the particular number of object images,change a color of the specific indication image.
 17. The non-transitorycomputer-readable medium according to claim 15, wherein the instructionsare further configured to, when executed by the processor, cause theprocessor to, when the dragging operation of dragging the specificindication image in the specific direction is performed in a state wherethe tail-end object image positioned at the tail end portion of the listimage in the scrolling direction is displayed in the particular positionin the display area, execute an extending-contracting operation of:extending the length of the specific indication image by a particularlength for a particular period of time; and thereafter returning thelength of the specific indication image to the specific initial length.18. The non-transitory computer-readable medium according to claim 17,wherein the instructions are further configured to, when executed by theprocessor, cause the processor to, when executing theextending-contracting operation, change a color of the specificindication image.